Acer pensylvanicum aka Striped Maple

Striped maple, Acer pensylvanicum, is a small deciduous maple from eastern North America. Gardeners also call it snakebark maple, moosewood or goosefoot maple. It grows wild from Nova Scotia and Quebec west to Minnesota and Wisconsin. In the Appalachians it reaches south to Georgia. It lives as an understory plant in cool, moist, rocky woods. It is the only snakebark maple native to North America; the others come from Asia.

In gardens it forms a large shrub or small tree, usually 15 to 25 feet (4.5 to 7.6 m) tall. The spread is similar, often up to about 20 feet (6 m). Old trees can reach 30 to 40 feet (9 to 12 m) in the wild. The crown is rounded or flat-topped and often uneven and open. Growth is slow.

The bark is the main attraction. Young trunks and branches are smooth and green-grey with long white vertical stripes. These stripes fade as the bark ages and turns reddish brown. Twigs shift from green to reddish, and the stalked buds are purplish red. The opposite leaves are large and simple, 5 to 8 inches (13 to 20 cm) across. Each has three forward-pointing lobes, a finely toothed edge and a shape like a goose's foot. New leaves may open with a pink tinge. In autumn they turn a clear, bright yellow.

Small, bell-shaped, yellow-green flowers hang in slender racemes in mid to late spring. Male and female flowers grow on separate plants. Bees visit them for early nectar. Paired samaras with widely spread wings follow in drooping clusters. They ripen from late summer into autumn.

This maple wants partial shade and copes with heavy shade. Full sun can scorch the leaves. It needs cool, moist, well-drained soil that is slightly acidic. Its roots are shallow and spread wide. It does best where summers are cool and struggles in hot southern climates. It dislikes drought, heat and air pollution. It is hardy in USDA zones 3 to 7 and rated H6 in the UK.

Use it in woodland gardens, along the edge of trees or as a shaded specimen. The striped bark gives winter interest. The cultivar 'Erythrocladium' has red winter twigs. Deer, moose and other mammals browse the shoots. Maples also host imperial moth caterpillars. Settlers once fed the leaves to cattle. Native Americans made arrows from the wood and medicinal teas from the bark. People also packed the leaves around stored apples and root crops.

The tree suits only sites that match its woodland origins. Mowers easily damage the thin bark, and stressed plants are prone to canker. Other diseases include verticillium wilt, leaf spots, tar spot, root rots and honey fungus. Pests include aphids, scale, borers and caterpillars. Mites and acer gall mite may also appear. No edible uses and no known hazards are recorded.